Amines are organic compounds currently very widely used in numerous sectors of industry, for example as catalysts or crosslinking agents in the field of polymer synthesis, and in particular polyurethane synthesis, or else as additives in lubricants, paints, and others.
One drawback of organic amines may in some cases arise from their odor, which is more or less strong, more or less pronounced, and more or less nauseating. Some amines even give off such strong and/or unpleasant odors that they must be handled in a closed chamber, or else even with breathing equipment intended for the technical personnel, which is accompanied by logistical problems and associated costs.
Thus, for example, amines, more particularly tertiary amines or mixtures of tertiary amines, are currently used in the manufacture of polymers, for example polyurethanes, for manufacturing car seats, for manufacturing cores for foundry molds, and others, to name but a few of the possible fields of applications.
More specifically, the manufacture of cores for foundry molds makes use of a process referred to as the “Ashland process” (or else the “cold box process”), in which process a binder comprising a polyol resin and an isocyanate is added to a mass of sand to be hardened. A polymerization agent is then injected in aerosol form into the mass of sand to be hardened containing the binder, causing instantaneous curing of the resin. The curing is obtained by a polyaddition reaction between the polyol resin and the isocyanate in the presence of the polymerization agent.
In this process, the polymerization agent used consists of amine(s) or a mixture of amines, and more particularly tertiary amines, which most often have strong, nauseating odors. When the amines are injected and curing is obtained, the excess amines are eliminated by a flow of rinsing air, before being treated. Inevitably, residual traces of amines are present and generate bad, bothersome odors which are just as damaging to the workers of the industrial sites.
In order to eliminate the release of malodorous compounds into the atmosphere, chemical scrubbing towers are generally used in foundries. These scrubbing towers make use of absorption techniques able to convert the malodorous molecules from the gas phase to the liquid phase by means of exchange columns. However, this treatment does not make it possible to eliminate, or at the very least effectively reduce, the unpleasant odor that these amines generate upstream, that is to say before the use thereof by the workers in the factories.
Patent application JP8302383 proposes a perfuming composition comprising at least one aldehyde, having a C6-C15 carbon-based chain, and at least one ester. This composition makes it possible to mask the bothersome odor of tertiary amines, and especially the tertiary amines used as polymerization agent in the production of polyurethane, by spraying this odorizing composition into the air of the chambers polluted by the odors of said amines.
International application WO2012/121359 proposes a deodorizing composition comprising at least one dicarboxylic acid and at least one tricarboxylic acid as active agents, and metal acid salts. This deodorizing composition is described as making it possible to eliminate amine odors. Indeed, the carboxylic acids and the metal acid salts are used to neutralize the amine residues which are thus salified.
Thus, none of the solutions currently known is able to overcome the abovementioned drawbacks, and there remains a real need to eliminate, or at least effectively reduce, the unpleasant odors that the amines, and in particular the tertiary amines, generate, by economical and simple means.